decorator.py

class Klass(object):

    def decorator(original_func):
        def func(*args):
            return [x * 10 for x in original_func()]
        return func

    @decorator
    def decorated_func():
        lists = [1, 2]
        return lists

    @decorator
    def decorated_func2():
        lists = [10, 20]
        return lists


klass = Klass()
print klass.decorated_func()
print klass.decorated_func2()

# [10, 20]
# [100, 200]

# デコレータの定義を後ろにするとエラーが発生

class Klass(object):

    @decorator
    def decorated_func():
        lists = [1, 2]
        return lists

    @decorator
    def decorated_func2():
        lists = [10, 20]
        return lists

    def decorator(original_func):
        def func(*args):
            return [x * 10 for x in original_func()]
        return func


klass = Klass()
print klass.decorated_func()
print klass.decorated_func2()

# Traceback (most recent call last):
#   File "decorator.py", line 65, in <module>
#     class Klass(object):
#   File "decorator.py", line 67, in Klass
#     @decorator
# NameError: name 'decorator' is not defined